Validation of the (Troponin-only) Manchester ACS decision aid with a contemporary cardiac troponin I assay

• Published in: The American journal of emergency medicine 2018-04, Vol.36 (4), p.602-607
• Main Authors: Va Den Berg, Patricia, Burrows, Gillian, Lewis, Philip, Carley, Simon, Body, Richard
• Format: Article
• Language: English
• Subjects: Acute Coronary Syndrome - diagnosis; Acute Coronary Syndrome - physiopathology; Acute coronary syndromes; Aged; Aged, 80 and over; Angina pectoris; Assaying; Biomarkers; Biomarkers - blood; Blood tests; Calcium-binding protein; Cardiac troponin; Chest Pain - diagnosis; Clinical decision rules; Decision Support Techniques; Emergency medical care; Emergency medical services; Emergency Service, Hospital - statistics & numerical data; Family physicians; Fatty acid-binding protein; Fatty Acid-Binding Proteins - blood; Female; Heart; Heart diseases; Hospitalization - statistics & numerical data; Hospitals; Humans; Laboratories; Male; Middle Aged; Myocardial infarction; Pain; Patients; Predictive Value of Tests; Prospective Studies; Secondary analysis; Sensitivity and specificity; Statistical analysis; Troponin; Troponin I; Troponin T; Troponin T - blood; United Kingdom
• ISSN: 0735-6757; 1532-8171
• DOI: 10.1016/j.ajem.2017.09.032

The Manchester Acute Coronary Syndromes (MACS) decision aid can ‘rules in’ and ‘rule out’ acute coronary syndromes (ACS) by combining a patient's symptoms with the results of a single blood test taken at the time of arrival in the Emergency Department (ED). The original model (MACS) included two biomarkers: high sensitivity cardiac troponin T (hs-cTnT) and heart-type fatty acid binding protein (h-FABP). A refined model without h-FABP was found to have comparable sensitivity but greater specificity. We sought to validate MACS and T-MACS using the contemporary Siemens Advia Centaur cardiac troponin I assay to increase usability in practice. This is a secondary analysis from prospective diagnostic cohort study at Stepping Hill Hospital, United Kingdom. Patients presenting with chest pain of suspected cardiac nature warranting rule out for ACS were included. All patients underwent hs-cTnT testing at least 12h after peak symptoms. The primary outcome was a diagnosis of ACS, defined as either prevalent acute myocardial infarction (AMI) or incident major adverse cardiac events (death, AMI or coronary revascularization) within 30days. Of 405 included patients, 76 (18.8%) had ACS. MACS and T-MACS had similar C-statistics (0.94 for each, p=0.36) and sensitivity (difference 1.3%, 95% CI −1.3 to 3.9%, p=1.00) but T-MACS had significantly greater specificity (difference 16.7%, 95% CI 14.6–18.9%, p